Fructose is obtained, on industrial level, mainly from corn, but it is also found in fruit and honey. Discovered in 1847 by the French researcher P.Dubrunfaut, it can be extracted from sucrose by dilute acids, giving rise to glucose and fructose and it takes the name of "invert sugar" because, unlike sucrose which is dextrorotatory, it polarizes to the left. It is also called "levulose".
It can also be obtained chemically from the oxidation of mannite.
Commercially it is in the form of a rather consistent brown liquid.
It is used as a sweetener by the food industry.
Dietary fructose intake increased significantly from 1970 to 2000 and during this period there was a 25% increase worldwide in the so-called "added sugars" (1). This is because fructose is sweeter than glucose and sucrose, while in beverages it serves to give the optimal sweet taste.
The increased consumption of fructose has increased, in parallel, with the spread of obesity, which suggests a relationship (2) and furthermore, in this article (3), fructose in the diet is indicated as a potential risk factor for cardiovascular diseases.
In the study conducted by Aeberli et al. (4), dietary factors, in particular fructose, were examined in relation to the body mass index, waist-hip ratio, plasma lipid profile, and LDL particle size in 74 Swiss schoolchildren aged between 6 and 14 years. In this study the plasma triglycerides were higher, HDL cholesterol concentrations were lower, and the size of the lipoproteins (LDL) of the particles were smaller in overweight children than in normal weight children. The fatter children had smaller sizes of LDL particles, and, even after being checked for adiposity, the fructose intake diet was the only dietary factor related to LDL particle size. In this study, fructose was free, and not sucrose, which was shown to be related to the effect of LDL particle size (5). Studies conducted on rodents, dogs and non-human primates that have a diet high in fructose or sucrose consistently demonstrate hyperlipidemia (6). The current report Aeberli and others, suggests that the higher intake of fructose by school-age children can have negative effects, with a future risk of cardiovascular disease, reducing the size of LDL particles.
References______________________________________________________
(1) Havel PJ. Dietary fructose: implications for dysregulation of energy homeostasis and lipid/carbohydrate metabolism. Nutr Rev 2005;63:133–57.
(2) Bray GA, Nielsen SJ, Popkin BM. Consumption of high-fructose corn syrup in beverages may play a role in the epidemic of obesity. Am J Clin Nutr 2004;79:537–43
(3) Nakagawa T, Hu H, Zharikov S, et al. A causal role for uric acid in fructose-induced metabolic syndrome. Am J Physiol (Renal Physiol) 2006;290:F625–31.
(4) Aeberli I, Zimmermann MB, Molinari L, et al. Fructose intake is a predictor of LDL particle size in overweight schoolchildren. Am J Clin Nutr 2007;86:1174–8.
(5) How bad is fructose? George A Bray
© 2007 American Society for Clinical Nutrition
(6) Havel PJ. Dietary fructose: implications for dysregulation of energy homeostasis and lipid/carbohydrate metabolism. Nutr Rev 2005;63:133–57